The Asherian War has ushered Earth and its population into a new age. Humankind has gone, giving rise to a tenuous society of other races once confined largely to shadows and stories. The new paradigm is overseen by the Celestials, whose terrestrial ambassadors, the Legacies, wield a potent and manifold elemental magic—one ruled by the astrological sign one is born under. They were instrumental in banishing the dragons—ravenous and mindless beasts—to the gloomier land of a place known as the Outer Edge.

Astraea, the powerful general of the Legacy Legion, cannot stand by when two massive dragons descend on the Legacy Compound and abduct her younger sisters. Leaping on one of their great scaly backs, becoming a willing captive to the darker margins of their world, she and her siblings undertake a shocking and revealing journey, one where prior deceptions are lifted, where alliances fall and former enemies become allies and where new, unexpected dangers are born.

Dragons, Astraea learns, are hardly the mindless creatures she knew them to be—they are, as one named Nemesis tells her, thoughtful seekers of peace, with a wholly different perspective on the Asherian War, and their banishment to the Outer Edge.

As Astraea and her sisters reconcile themselves to this new reality, the fae king, Asher—so named for the war, and who is very much in love with Astraea—pursues them to the Outer Edge. Though he can be pompous and presumptuous, there is no doubt Astraea herself is drawn to him. Now, as she cautiously opens her heart, and arms herself with new understanding, she and the others must also prepare to confront those who stand in the way of peace.